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JNCIP-ENT lab 5 of 19

BGP communities and policy

Stop a network being a free transit by labelling every route with a community at the edge, then control exports, ISP behaviour and AS path filtering from those labels.

Run this lab

It needs Standard: its 6 nodes are set to 12 vCPU and 12,288 MB in total.

In your workspace: Shared, then JNCIP-ENT JN0-650 guided labs, then 05 - BGP communities and policy

Run it on Standard from £5 a day

The free demo can’t run it: it has 6 vCPU and 8 GB, and this lab’s nodes need 12 vCPU and 12,288 MB together. Every lab plan includes every guided lab.

Level
Advanced
Time
About 90 minutes
Nodes need
12 vCPU, 12,288 MB
Smallest plan
Standard

The scenario

Northmere has grown into a small regional network. It buys transit from ISP-A and ISP-B, peers with a neighbour (PEER), and sells connectivity to a customer (CUST). All the sessions are up, but there's no policy, so Northmere is giving every network a free ride over its links. You'll label every route with a community when it arrives, and then let those labels decide where it goes. That's how networks of any size keep policy manageable: the decision is made once, at the edge, and every other router just reads the label.

ASDeviceRoutes
64500R1, R210.60.0.0/16, an aggregate on both
64501ISP-A (transit)203.0.113.0/24, 100.64.9.0/24
64502ISP-B (transit)198.51.100.0/24, 100.64.30.0/24
64503PEER (peer)172.31.200.0/24
64504CUST (customer)192.168.100.0/24
LinkAddresses
R1 to R210.0.12.0/30, with loopbacks 10.255.0.1 and .2
R1 to ISP-A198.18.1.1 and .2
R2 to ISP-B198.18.2.1 and .2
R1 to CUST198.18.4.1 and .2
R2 to PEER198.18.5.1 and .2

The plan for communities:

CommunityMeaning
64500:100Learned from transit
64500:200Learned from a peer
64500:300Learned from a customer

What you’ll practise

  • Add, match and delete communities
  • Write customer, peer and transit export rules
  • Use community and AS path regular expressions
  • Explain the well-known communities
  • Influence an ISP with an action community

The tasks

  1. Label routes as they arrive
  2. Let the labels decide
  3. Match several communities with a regular expression
  4. Respect the well-known communities
  5. Use your ISP's action community
  6. Filter on the AS path

The Lab Tasks pane has the scenario, these tasks, the checks to run, hints and the full solution.

Topology and devices

The network as it opens in EVE-NG, drawn from the lab’s own canvas, and the image each node runs.

Topology of BGP communities and policy6 nodes, 6 links. Every link is listed as text below the diagram.R1R2ISP-AISP-BCUSTPEERge-0/0/1Gi0/0ge-0/0/1Gi0/0ge-0/0/2Gi0/0ge-0/0/2Gi0/0ge-0/0/0ge-0/0/0Gi0/1Gi0/1
6 nodes, with the interface names each link uses.
Every link, as text
  • R1 ge-0/0/0 to R2 ge-0/0/0
  • R1 ge-0/0/1 to ISP-A Gi0/0
  • R2 ge-0/0/1 to ISP-B Gi0/0
  • R1 ge-0/0/2 to CUST Gi0/0
  • R2 ge-0/0/2 to PEER Gi0/0
  • ISP-A Gi0/1 to ISP-B Gi0/1
Nodes in BGP communities and policy, with the image each runs and the vCPU and RAM it’s set to
NodeDeviceImage in Add NodeSet to
R1Juniper vJunos-routervjunosrouter-24.2R1-S2.54 vCPU, 5,120 MB
R2Juniper vJunos-routervjunosrouter-24.2R1-S2.54 vCPU, 5,120 MB
ISP-ACisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB
ISP-BCisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB
CUSTCisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB
PEERCisco IOSvvios-adventerprisek9-m.spa.159-3.m91 vCPU, 512 MB

How to open this lab

  1. Sign in to your workspace at lab.cloudlabbox.com.

  2. In File Manager, open Shared, then the folder JNCIP-ENT JN0-650 guided labs.

  3. Open 05 - BGP communities and policy and start its nodes, then open Lab Tasks for the scenario and the steps.

The lab is read-only. You can start the nodes and configure the devices, but changes to the topology can’t be saved. To change it, rebuild it in your own folder.

More JNCIP-ENT labs

All JNCIP-ENT labs

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CloudLabBox is independent of Cisco and Juniper Networks. The lab follows exam topics and isn’t vendor training material; vendor names identify the exams and the images in the workspace.